This dissertation discusses two topics in Korean morphology: (i) word formation in Korean and constraints on word formation, and (ii) interface phenomena between word formation and syntax, and between word formation and phonology. Chapter 1 presents the goal and scope of this dissertation. Chapter 2 discusses word formation in various lexical categories of Korean. As in other languages, words in Korean are formed by derivation and compounding. We demonstrate that nouns and adverbs can be formed by derivation and compounding, that verbs can be formed by derivation and compounding, but involve inflection, and that postpositions can be formed by compounding. Chapter 3 discusses blocking phenomena in Korean. Blocking is a kind of output filter on word formation. We demonstrate that blocking functions to avoid synonymy or homonymy. Chapter 4 discusses interface phenomena between word formation and syntax. Certain constituents in Korean have the same shape in both the lexicon and the syntax. For example, derived nouns resemble verbal nominalizations, noun compounds resemble phrasal nominalizations, and the verb + noun constructions appear identically as either noun compounds or noun phrases. Although these constructions resemble each other, they differ in certain ways. We explore different properties of these formally identical structures. The verb + verb constructions and the noun + verb constructions are ambiguous in structural category. We explore whether these constructions are words or phrases, and examine what properties they have. Chapter 5 discusses other interface phenomena between word formation and phonology. We explore what environments contraction is formed in and how contraction is formed. In addition, we note several inadequacies of lexical phonology. Chapter 6 summarizes and concludes this dissertation. All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner. ScholarSpace is the institutional repository for the University of Hawaiʻi at Mānoa and is maintained by Hamilton Library.